* Introduction


* System setup steps

1. update system packages:

   #+begin_src shell
   apt-get update
   apt-get upgrade
   #+end_src

2. install some system tools

   #+begin_src shell
   apt-get install aptitude htop sudo
   #+end_src

3. add ~root~ user to sudoers group:

   #+begin_src shell
   usermod -aG sudo root
   #+end_src

** Firewall

1. install ~ufw~:

   #+begin_src shell
   apt-get install --yes ufw
   #+end_src

Or configure the firewall using ~iptables~.
